Math, asked by pak3, 1 year ago

ap a=7anda13=35 find d and sn

Answers

Answered by shivani12320
1
A=7
A13=35
A+12d=35
7+12d=35
12d=5
D=5/12

Sn=n/2[2a+(n-1)d]
=N/2(2*7(N-1)5/12]
=N/2*14(N-1)*5/12
=7n(n-1)5/12
12/5=7n^2 - 7n
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